The present invention relates to a series of new thiazolidine derivatives, which exhibit anti-diabetic activity in mammals, and provides methods and compositions using them, as well as processes for their preparation.
Thiazolidine derivatives which can reduce blood sugar levels have been described, for example, in Japanese Patent Application Kokai No. Sho 55-22636 (Tokko No. Sho 62-42903), European Patent Publications No. 139 421 and 207 581, Japanese Patent Application Kokai No. Sho 61-36284 and No. Sho 62-5980 and Y. Kawamatsu et al., Chem. Pharm. Bull., 30, 3580-3600 (1982). These prior compounds all differ structurally from the compounds of the present invention.
We have now discovered a series of new thiazolidine derivatives, which have a particularly good activity, in some cases much better than the prior compounds referred to above. In particular, the compounds of the present invention show a significant ability to suppress hepatic gluconeogenesis, which ability is expected to result in a level of reduction in fasting blood sugar levels which is substantially better than is achieved by the compounds disclosed in the prior art referred to above.